Stoker mechanism



Dec. 31, 1935. G, REID v STOKER MECHANISM Filed Feb. 24, 1932 3 Sheets-Sheet? GRA/V 7' 'D INVENTOR.

BY M

ATTORNEY Dec. 31, 1935. G, REID l 2,026,400

' sToxER MECHANISM Filed Feb. 24, 1952 3 Sheets-Sheet 5 Patented Dec. 31, 1935 PATENT GFFICE 2,026,400 y STOKER MECHANISM Grant Reid, Baltimore, Md., assignor to The Standard Stoker Company, Incorporated, a corporation of Delaware Application February 24, 1932, Serial No. 594,817

9 Claims.

This invention relates generally to operating mechanism for a screw conveying system, and more particularly to operating mechanism comprising a reciprocating pressure uid engine'and an associated clutch mechanism for a screw conveying system of a locomotive stoker.

Mechanical stokers are liable to become clogged and stopped either by congestion or by the pressure of extraneous matter, such as scraps of metal, being accidentally intermixed with the fuel. When this occurs it becomes necessary to temporarily reverse the direction of the screw conveying means, and to this end the clutch must be released. The stalling will occur on the power stroke of the engine, and as the clutch mechanism is then under pressure its manual disengagement is difficult or impossible, and it has been necessary to provide means for relieving this pressure. It is therefore, the principal object of this invention to provide an arrangement of a reciprocating engine and clutch mechanism that will permit easy manual reversal of the screw conveying means, in the event of the stoker being stopped by clogging, during the power stroke of the engine piston and while pressure is applied thereto.

It is a further object of the invention to provide improved and novel clutch mechanism that will obviate the necessity of providingV added means for relieving the pressure on the engine piston, in order that the clutch connecting the engine with the screw conveying means may be released.

Still another object of the invention is the pro- Vision of a clutch and means for controlling the clutch that is simple in design, compact, composed of relatively few parts, efficient in operation and that may be readily disassembled for purposes of repair and replacement of parts.

Other and further objects of the invention contemplate the particular features of construction, combinations of elements and arrangement of parts hereinafter more fully described and illustrated in the accompanying drawings, in which Fig. 1 is a vertical longitudinal central sectional view of a portion of a locomotive and its tender, illustrating parts of a stoker, which are also in section, mounted therein;

Fig. 2 is a plan view of the driving unit for the fuel conveyor in the Stoker conduit; A

Fig. 3 is an enlarged plan view of the clutch and a clutch control lever with part of the clutch casing broken away to show the interior; y

Fig. 4 is an enlarged vertical sectional view taken on line 4--4 of Fig. 2 illustrating the clutch mechanism and clutch control means in detail;

Fig. 5V is an enlarged vertical sectional view taken on line 5 5 of Fig. 2 showing the single motor and part of the power transmitting mechanism connecting the motor with the fuel conveyor in the stoker conduit;

Fig. 6 is a vertical sectional View taken on line 6--6 of Fig. 4;

Fig. 7 is an enlarged sectional view taken on line I-1 of Fig. 6.

In the drawings, the locomotive is indicated generally by the letter A and is provided with the rebox I0, having a backhead I I with a firing opening I2 therethrough. 'Ihe tender isdesignated generally by the letter B and includes a fuel bin I3 and a deck III provided with a longitudinal central opening I5. Slide plates I6 are mounted in the opening I5 and may be moved from covering position to permit gravity feeding of the fuel;

Mounted on the locomotive and tender is a stoker. designated by the letter s, a preferred embodiment of which is illustrated in the drawings and hereinafter described, but it will be obvious as the/description proceeds that the invention is equally adaptable to stokers of various types and designs.

The stoker s includes a transfer conduit I'I, which comprises the trough portion I8 and the tubular extension I9 leading forwardly fromthe trough portion I8.

A riser conduit 22 is rigidly attached to the `backhead of the locomotivek by suitable means, such as the tie bars 23, and communicates at its forward end with the firing opening I2'. The'conduit 22 extends rearwardly and downwardly,vterminating beneath the cab deck 69 in a spherical split ange 24 arranged to receive the ball member 25 of the tubular extension I9 thereby affording universal movement between the transfer conduit II and the riser conduit 22.

The riser conduit 22 discharges upon a distributor plate 26, over which fuel is projected and distributed over the re in the rebox by means of a pressure fiuid blast issuing from the jet nozzles 21 in the distributor head 28.

A suitable sectional conveyor screw 3| comprising the sections 32 and 33 is rotatably mounted in the conduit system comp-rising` the transfer conduit I'I and riser conduit 22, the sections being universally connected as by a short screw section 34. The sectional conveyor screw 3l is operated from its rear end through suitable gearing (not shown) and shafting (not shown) connects the gearing with driving mechanism comprising a clutch designated as a whole by numeral 80, a shaft 8|, a gear 82 and a rack 83 by a pressure fluid operated motor, represented as a unit by numeral 84, having a single reciprocating piston therein. This driving mechanism is mounted rigidly as a unit separate from the stoker conduit upon the locomotive frame 58.

The motor, best illustrated in Fig. 5, comprises a cylinder 88 within which reciprocates the piston 85 provided with a rod 91. Steam is delivered to the motor at 88, and exhausted at 89. The distributing valve 90 is of D form, and alternately connects ports 9| and 92 with the opposite ends of the cylinder and with the exhaust port 89. This valve is shifted by means of a pair of differential pistons 93, 94, fixed upon its stem and reciprocating in suitable cylinders, steam entering at the port 88 being at all times eifective upon the adjacent faces of the two pistons and normally holding the valve 90 in the position shown in Fig. 5, representing the power stroke of the motor.

A controlling valve of D form is mounted in a cylindrical valve chamber 96 formed in the head of the cylinder 88 and in axial alinement with the cylinder. The valve 95 is provided with a stem 91 extending into the cylinder 86 and loosely fitting within an axial aperture 98 in the piston rod 81 and being provided at its inner end with a stud or crosshead 99. As the piston 85 completes its power stroke, moving in the direction indicated by the arrow in Fig. 5, the stem 91 is met by the bottom of the aperture 98 and the valve 95 is thereby shifted to the left. Upon the completion of the return stroke of the pist0n 85, the stud or cross head 99 is engaged by a detent mounted upon a face of the piston and shown as taking the form of an apertured plate |00, and the valve 95 is shifted to the position of Fig. 5.

A port |0| connects the steam passage leading from the port 88 to the valve chamber 98, and a steam passage |02 leads from this chamber to the end of the cylinder within which the piston 93 reciprocates. An exhaust passage |03 leads from this cylinder to the chamber 98 and is controlled by the valve 95, the cavity of which connects it at suitable times with an exhaust passage |84 leading to the main exhaust passage of the motor. The valve 95 is provided with a projecting stem |05, snugly fitting and reciprocating in a pocket in the casing within which this valve is housed, and a duct |96 connects this pocket with the cylinder 8E.

With the parts in the position shown in Fig. 5I the passage |02 is closed by the valve 95, and the exhaust passage |03 is covered by the rim of the piston 93. The passage 9| being connected with the exhaust port 89, pressure in the pocket which receives the stem |05 is relieved. Upon the shifting of the valve 95 to the left, pressure is applied to the outer face of th-e piston 93, and preponderates over the constant pressure upon the inner face thereof because of the counterbalancing action upon the inner face of the piston 94, forcing the valve 90 downwardly and thereby reversing the direction of the piston 85. A relief passage |01 leads from the rearward end of the cylinder, within whichthe piston 94 reciprocates, to the passage leading to the exhaust port 89.

The piston 81 is rigidly connected to the rack 83 whichgreciprocates transversely of the locomotive within an enclosed casing |08 formed by the rack housing |89 and rack housing cover ||0. The gear 82 meshes with the rack 83 and is fixed to the forward end of the shaft 8| which is mounted longitudinally of the locomotive, whereby reciprocatory motion of the rack 83 causes oscillatory movement of the shaft 8 I. The shaft 8| is vertically supported by a bearing split 5 horizontally to provide a lower half and an upper half ||2, The lower half bearing is mounted in the rack housing cover ||9 and the upper half ||2 in a cover ||3. The cover ||3 is secured to the rack housing cover ||0 and forms a part of the chamber in which the gear 82 is mounted. Keys I4 prevent rotation of the bearing with the shaft 8|.

A clutch casing I5 is mounted for rotation in opposite directions or floatably mounted on the rear end of the shaft 8|. A plurality of lugs |31 on the rear end of the clutch casing form one jaw of a universal joint of the shafting (not shown) connecting the clutch casing and the stoker driving unit. The clutch casing ||5 is 20 composed of front and rear end plates H6 and ||1, respectively, and a cylindrical body portion H8. Proper alinement of the end plates and body portion is assured by means of dowels ||9, and the end plates and body portion are rigidly 25 secured together by means of a plurality of spaced through bolts |20. The front end plate H6 is provided with a hub |2|, and a bushing |22, pressed in the hub, rides on the shaft 8|. A second bushing |23, pressed in an enlarged bore 3o |24 in the shaft 8|, rides on a boss |25 which projects into the clutch casing from the rear end plate ||1. By this construction the clutch casing is carried by the shaft 8|. The end |48 of the hub |2| butts against a boss |49 on the rack 35 housing cover and the cover ||3 to prevent forward movement of the clutch casing on the shaft 8|. Thrust washers |28 and |21 prevent rearward movement of the shaft 8 and thrust washer |28 inserted between the shoulder |29 on shaft 40 8| and a circumferential flange |30 on the bushing |22, also prevents forward movement of the shaft 8| and rearward movement of the clutch casing.

A disk |3| is integral with the rear end plate 45 ||1 and mounted on the inside surface thereof. A similar disk |32 is integral with the front end plate ||6 and mounted on the inside surface thereof. The disks |31 and |32 or clutch elements are shown and described as being integral with the ends of the clutch casing, but they may be separate therefrom and fixed thereto in any desirable manner. The adjacent faces |33 and |34, respectively, of the disks |3| and |32 are spaced a fixed distance from each other and each of the adjacent faces are provided with a series of equally spaced radial projections or teeth, the teeth on one face being disposed for engagement in a direction opposite to that of the teeth on the other face. A third disk member or plate |35 is carried by the shaft 8|, rotates therewith and is arranged to slide longitudinally thereof. The perimeter of the shaft 8| in transverse section, rearward of the shoulder |29, is hexagonal in shape (Fig. G) and an opening |35 through the disk |35 corresponds to the shape of the perimeter of the shaft 8|, whereby the said disk will rotate with the shaft; but the opening |36 is of such dimensions as to permit free longitudinal movement of the disk |35 on the shaft 8|. The disk |35 is positioned intermediate the faces |33 and |34 respectively, of the disks |3| and |32. Each of the forward and rearward surfaces |38 and |39 of the disk |35 is provided with a series of equally spaced radial teeth. The teeth on the forward 75 surface |38 of the disk |35 correspond in number and dimensions to the teeth on the face |34 of the disk |32, and the teeth on the rearward surface |39 of the disk |35 correspond likewise to the teeth on the face |33 of the disk |3| Forward movement of the disk |35 on the shaft 8| causes the teeth on the surface |38 of said disk to engage the teeth on the disk |32 for rotating the clutch casing ||5 in one direction, and rearward movement of the disk |35 engages the teeth on the surface |39 of the disk |35 With those on the disk |3| to rotate the clutch casing in the opposite direction.

It will be noted in Figure 7 Vthat the depth of the teeth on the clutch disks is small with relation to the pitch thereof, and that engagement or disengagement of the intermediate disk |35 with either of the end disks |3| and |32 may be had with slight longitudinal movement. The leading edges. |40 of the clutch teeth are disposed in planes passing through the axis of shaft 8| whereby the teeth are not wedged in one another when they are in engagement.

Shifting of the intermediate disk is provided for in the following manner. A pin |4|, rigid with the intermediate disk |35, extends through elongated slots |42 in the shaft 8| and a slot |43 in a shifting rod |44. When the shaft 8| is rotated, the sides of the slot |42 contact with the pin |4| causing the pin to rotate with theshaft, and the pin |4| engages the sides of the slot |43 in the shifting rod to rotate the shifting rod with the shaft. The rod |44 is mounted in the shaft 8| and is supported at its rear end in a bushing |45 pressed in the boss |25 on the clutch rear end plate and at its forward end by means'of a collar |46, xed on the rod, riding in a recess |41 in the shaft 8|.

The pin4 |4| extends through a collar |63 mounted on the rod |44 to rotate therewith. The collar |63 is arranged to slide freely longitudinally of the rod |44. A spring |64 is interposed between a shoulder |65 on the collar |63 and a shoulder |12 in the enlarged bore |24 and tends to hold the teeth on the surface |39 of the disk |35, by means of collar |53 and the pin |4|, in engagement with the teeth on the disk |3|. A spring |1|, interposed between a shoulder |13 on the shifting rod |44 and the bottom of the enlarged bore |24 tends to maintain the rod in its most rearward position, and hold the teeth on the surface |38 of the intermediate disk out of engagement with the teeth on the disk 32. The shifting rod |44 is moved longitudinally of the shaft 8| by manually rocking a lever |50 pivoted to the cover H3 at |5I. A bar can be inserted in a recess |52 in the upper end of the lever to decrease the manual effort required to disengage the clutch elements. The lower end of the lever |50 is pivoted at |53 to a lug 54 on one end of an L-shaped bar |55. The other end of the L-shaped bar moves the rod |44 when the lever |50 is rocked by contacting with a circumferential shoulder |56 on the collar |46 and a washer |51 fixed by a lock nut |58 to the shifting rod.

A latch |59 hinged to the cover |13 is held in Contact with notch |66 or notch |6| in the quadrant |62 on the L-shaped bar |55 by a spring |69 to maintain the clutch shifting mechanism in such positions that the fuel conveyor in the stoker conduit will be held, respectively in inoperative position or fuel forwarding position. The spring |69 is of sufficient tension to normally hold the latch |59 engaged in notches |60 and |6| whereby the clutch shifting mechanism is held in either of two locked positions, which are,

a position so that the clutch disk |35 is not in engagement with either of thedisks |3| and |32 and a position whereby the disk 35 engages the 5 disk 3| to cause the conveyor to move fuel forward in the stoker conduit.

A flange |61 on the cover ||3 prevents dust and water from getting into the driving mechanism through the end |48 of the hub |2| and the 10 boss |49. The driving and clutchmechanism is lubricated by means of pipe lines (not shown) leading from the ducts |68 to an oil reservoir.

Assuming the stoker motor to be operating and the intermediate clutch disk in neutral position 15 or the position shown in Fig. 4, and it is desirable to advance fuel through the stoker conduit, the upper end of the lever |50 is rocked forward `moving the L-shaped bar rearward causing the latch |59 to disengage the notch |60 and 20 engage the notch |6|. The shifting rod is also moved rearward permitting the collar |63, the pin |4| and the intermediate disk |35 to be forced rearward by the tension of spring |64, causing the teeth on the rear surface of the intermediate 25 disk to engage the teeth on the disk |3|. During oscillation of the disk 35 the leading faces of the teeth thereon engage the leading faces of the teeth on the disk I 3| during rotation of the disk |35 in one direction, causing the clutch 30 casing and the fuel conveyor to rotate therewith; and when the disk I 35 rotates in the opposite direction, the rear edges |10 (Fig. 7) of the teeth on the disk |35 slip over the rear edges of the teeth on the disk |3| causing the clutch casing 35 to stand still until the leading edges of the teeth are again engaged by rotation of the disk |35 in the first mentioned direction. As the teeth on one disk slip over the teeth on the other disk the intermediate disk, the pin |4|, the collar |63 40 and the spring |64 vibrate longitudinally a distance corresponding to the depth of the teeth.

To reverse the rotation of the fuel conveyor in the Stoker, the upper end of the lever |50 is rocked to its extreme rearward position. Such 45 movement of the lever |50 causes forward movement of the shifting rod |44 by means of the L- shaped bar |55 and the rear edge |66 of the slot |43 in the shifting rod contacts with the pin |4| pulling said pin and the intermediate disk for- 50 ward to engage the teeth on the forward surface |38 of said disk with the teeth on the disk.,|32. The lever |50 must be held manually in this position until it is desirable to render the fuel conveyor inoperative or place the clut-ch mecha- 55 nism in the fuel forwarding position.

I claim:

1. In combination, a drive shaft, means for imparting oscillatory movement to said drive shaft, a clutch including a casing freely carried by said drive shaft, two spaced clutch members rigid with the casing, a third clutch member mounted on said drive shaft and arranged to oscillate therewith, and means for sliding said third clutch member longitudinally along said 65 shaft, independently of the direction of rotation of said oscillating driveshaft, in one direction to engage one of said spaced clutch members for rotating said casing in one direction and in the opposite direction to engage the other of said spaced clutch members for rotating said casing in the opposite direction.

2. In combination, a drive shaft, means for imparting oscillatory movement to said drive shaft, a casing freely carried by said drive shaft,

a pair of driven members rigid with the casing, a drive member mounted on said drive shaft to oscillate therewith and means for sliding said drive members longitudinally along said shaft in either direction independently of the direction of rotation of said oscillating drive shaft to selectively engage either of said driven members to cause rotation of said casing.

3. In combination, a drive shaft and means for oscillating said shaft, a driven shaft, a clutch interposed between said shafts comprising a oasing carried by the drive shaft and mounted thereon for rotation in opposite directions, a pair of spaced clutch members rigid with the casing, a third clutch member carried by said drive shaft, means for sliding said third clutch member longitudinally along said drive shaft in either direction independently of the direction of rotation of said oscillating drive shaft to selectively engage either of said spaced clutch members to cause rotation of the driven shaft in opposite directions and means arranged to retain said third clutch member in position for engagement with one of said spaced clutch members and out of engagement with the other of said members.

4. In combination, a drive shaft and means for continuously oscillating said shaft, a driven shaft, and a clutch interposedv between said shafts comprising a casing mounted on the drive shaft for rotation in opposite directions, means arranged to secure said casing on said drive shaft with respect to relative longitudinal movement, a plurality of spaced clutch members rigid with the casing,4 a member carried by the drive shaft and arranged to oscillate therewith and means for sliding said last named member longitudinally along said drive shaft in either direction independently of the direction of rotation of said oscillating drive shaft to selectively engage either of said spaced clutch members to cause rotation of the driven shaft in opposite directions.

5. In combination, a drive shaft having a longitudinal bore therethrough and a plurality of elongated slots therein, a driven shaft, a clutch interposed between said shafts having a casing rotatably mounted on the drive shaft, means for continuously oscillating said drive shaft, a plurality of spaced clutch members rigid with the casing, a clutch member on the drive shaft arranged to oscillate therewith, a rod extending thrgughout the bore in the drive shaft and having an opening therethrough, a pin on the last named clutch member extending through the slots in the drive shaft and the opening in said rod and means for shifting said rod longitudinally thereby engaging the last named clutch member with either of the first mentioned members independently of the direction of rotation of said oscillating drive shaft to cause rotation of said casing.

6. In combination, a drive shaft, means for continuously oscillating said drive shaft, a driven shaft, a clutch interposed between said shafts having a casing, a plurality of spaced clutch members rigid with the casing, and a clutch member intermediate said members arranged to rotate with the drive shaft and to slide longitudinally thereon in either direction independently of the direction of rotation of said oscillating drive shaft, a rod mounted within the drive shaft, means operatively connecting one end of the rod with the last named clutch member, and a lever operatively connected to the other end of said rod for shifting the same, thereby engaging the last named clutch member with either of the first mentioned members to cause rotatio-n of the casing in opposite directions.

7. In combination, a drive shaft, means for continuously oscillating said drive shaft, a driven shaft, a clutch interposed between said shafts having a casing, a plurality of spaced clutch members rigid with the casing, and a clutch member intermediate said members arranged to oscillate with the drive shaft, and means for shifting said last named me'mber longitudinally of the drive shaft independently of the direction of rotation of said oscillating drive shaft for selectively engaging the last named member with either of the first named members to cause rotation of the casing in opposite directions, said means comprising a rod operatively connected at one end to the intermediate clutch member, and a pivoted lever operatively connected to the other end of said rod, and means for maintaining the shifting means in one of a number of locked positions.

8. In combination, a drive shaft, means for continuously oscillating said drive shaft, a driven shaft, a clutch interposed between said-shafts having a casing, a plurality of spaced clutch members rigid with the casing, and a clutch member intermediate said members arranged to oscillate with the drive shaft, means arranged to maintain the last named member in engagement with one of the first named members, and means for shifting the intermediate clutch member longitudinally of the drive shaft independently of the direction of rotation of said oscillating drive shaft for selectively engaging the intermediate clutch member with either of the rst named members to cause rotation of the casing in opposite directions comprising a rod operatively connected to said intermediate member, and a lever operatively connected to said rod, and means for maintaining the shifting means in locked position.

9. In combination, a driving member, means for imparting oscillatory movement to said driving member, a driven member, a pair of spaced plates carried by said driven member and each provided with clutch members, a clutch member on said driving member arranged to oscillate therewith and means for sliding said third clutch member longitudinally along said driving member to engage the clutch members on either of said spaced plates independently of the direction of rotation of said driving member for operating said driven member.

GRANT REID. 

